It sounds like if you change the code in post #3 with this, it should do what you described. You can run it from any sheet.
Sub Clear_All_Sheets()
Dim lr As Long, j As Long
lr = Sheets("Items").Cells(Rows.Count, 4).End(xlUp).Row
For j = 1 To lr '<---- The sheet names to be cleared are in Sheet Items from cell D1 on down. If they start in cell D2, change the 1 to a 2.
On Error Resume Next '<---- If a Sheet does not exist or the spelling is wrong, code continues
With Sheets("Items")
Sheets(.Range("D" & j).Value).Range("A1:B1").ClearContents '<----- Change the "A1:B1" to the range that you want cleared.
End With
Next j
End Sub
If the range to be cleared is not a single block of cells, it needs to be changed. Let us know the range(s) to be cleared.
Try that on a copy of your workbook
There is a faster way if all the ranges to be cleared are the same.